Mechanical writing instrument

ABSTRACT

A mechanical writing instrument in which a carrier supporting an ink cartridge or the like is received by and threadably engages a driver tube rotatably positioned on a sleeve by a snapring. Interengageable means provide a connection between the carrier and the sleeve which permits relative axial movement therebetween while preventing rotary movement in response to rotation of the driver tube relative to the sleeve alternately to extend and retract the cartridge with reference to the sleeve. The assembly may be completed by a decorative two-part casing and a nose through which the point of the writing instrument may protrude.

llnited States Patent 72] Inventor Gino Carmen DiSpirito Hasbrouch Heights, NJ. [21] Appl. No. 885,421 [22] Filed Dec. 16, 1969 [45] Patented Dec. 28, 1971 [73] Assignee Kreisler Manufacturing Corporation North Bergen, NJ.

[54] MECHANICAL WRITING INSTRUMENT 18 Claims, 1 1 Drawing Figs.

[52] U.S.Cl 401/116 [51 Int. Cl B431: 24/06 [50] Field ofSearc 40l/68,78, l 16 [56] References Cited UNITED STATES PATENTS 3,272,184 9/1966 Crowley 401/116 3,436,160 4/1969 Lanoie ABSTRACT: A mechanical writing instrument in which a carrier supporting an ink cartridge or the like is received by and threadably engages a driver tube rotatably positioned on a sleeve by a snapring. lnterengageable means provide a connection between the carrier and the sleeve which permits relative axial movement therebetween while preventing rotary movement in response to rotation of the driver tube relative to the sleeve alternately to extend and retract the cartridge with reference to the sleeve. The assembly may be completed by a decorative two-part casing and a nose through which the point of the writing instrument may protrude.

PATENTED names 191;

SHEET 1 BF 2 .II I I'Illi-rlllll r INVENTOR.

67/70 .ZZ'Sk/r/TO I'TTORNEYS PATENTED DEC28 I97:

SHEET 2 OF 2 0 5 W N? R WW 0 m5 Km [MM MECHANICAL WRITING INSTRUMENT BACKGROUND OF THE INVENTION There are known in the prior art writing instruments of the type in which an ink cartridge is adapted to be shifted between a retracted position at which its point is housed by the nose of the assembly and a writing position at which the point protrudes beyond the end of the nose. The less expensive mechanisms are arranged so that the cartridge can be snapped axially into writing position against the action of a spring and then retracted in response to a second operation of the actuating element such as push button or the like. Instruments of this type have relatively short life and in many instances are not as appealing to customers as are instruments of the type wherein the writing point is exposed and retracted in response to relative rotary movement between two parts of the assembly.

In writing instruments of the type wherein the point is extended and retracted in response to relative rotary motion between parts of the assembly, it is desirable that the rotary motion required to move the point between the two positions be relatively small. Further, it is necessary that the point he firmly held in the writing position so that it will not back off or entirely retract in response to pressure on the point. Many attempts have been made in the prior art to provide a writing instrument of this type. The most successful attempts have involved structures employing a multiplicity of parts. Owing to the large number of parts making up the mechanisms they are complex and are consequently expensive to manufacture. In addition they are inherently subject to mechanical failures and are not readily repairable.

I have invented a mechanical writing instrument which overcomes the defects of writing instruments of the type in which the point is extended or retracted in response to a rotary movement. My mechanism employs a surprisingly small number of parts. It is simple both in construction and in operation. It is relatively inexpensive to manufacture. It is rugged and has a long life.

SUMMARY OF THE INVENTION One object of my invention is to provide a mechanical writing instrument which overcomes the defects of instruments of the prior art of the type in which the point is extended and retracted in response to a rotary movement.

Another object of my invention is to provide a mechanical writing instrument of the rotatable type which employs a minimum number of parts.

A further object of my invention is to provide a mechanical writing instrument which is simple in construction and in operation.

Still another object of my invention is to provide an mechanical writing instrument which is rugged and which has a long life.

Yet another object of my invention is to provide a mechanical writing instrument which is inexpensive to manufacture.

Other and further objects of my invention will appear from the following description.

In general my invention contemplates the provision of a mechanical writing instrument in which a driver tube rotatably positioned on a sleeve by a snap ring located in a groove on the sleeve threadably receives an ink cartridge carrier connected to the sleeve for rotary movement therewith and for axial movement relative thereto. In response to relative movement between the driver tube and the sleeve in one direction the point of the ink cartridge is exposed and in response to an opposite relative rotary movement of the driver tube and sleeve the point is retracted. My assembly may be provided with a decorative casing held in position on the sleeve by a nos and a cap frictionally received by the operating mechanism assembly.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings which form part of the instant specification and which are to be read in conjunction herewith and in which like reference numerals are used to indicate like parts in the various views:

FIG. I is a perspective view of my mechanical writing instrument with the cap showing in phantom.

FIG. 2 is an exploded perspective view illustrating the parts of the operating mechanism of my improved mechanical writing instrument.

FIG. 3 is a longitudinal sectional view of my mechanical writing instrument illustrating the relative positions of the parts with the point extended.

FIG. 4 is a sectional view of my mechanical writing instrument taken along the line 4-4 of FIG. 3 and drawn on an enlarged scale.

FIG. 5 is a sectional view of my mechanical writing instrument taken along the line 5-5 of FIG. 3 and drawn on an enlarged scale.

FIG. 6 is a sectional view of my mechanical writing instrument taken along the line 6-6 of FIG. 3-and drawn on an enlarged scale.

FIG. 7 is an exploded perspective view of the operating mechanism of a modified form of mechanical writing instrument.

FIG. 8 is a sectional view of the form of my writing instrument illustrated in FIG. 7 showing the mode of operation of a part of the mechanism.

FIG. 9 is a perspective view of yet another form of driver tube which I might employ in my mechanical writing instrument.

FIG. 10 is a fragmentary perspective view illustrating a further embodiment of my means for retaining cap on my mechanical writing instrument.

FIG. 11 is a sectional view with parts removed illustrating the cap retaining means shown in FIG. 10.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings my mechanical writing instrument indicated generally by the reference character 10 includes a carrier 12 having an elongated body provided with an axial bore 14. One end of the carrier 12 is provided with external threads 16 adapted to be engaged by internal threads 18 of a fitting 20 which supports an ink cartridge 22 or the like having a point 24. Preferably I provide fitting 20 with a serrated head 24a to facilitate placing of the cartridge 22 in the carrier 12 as required.

I form the central portion of the carrier 12 with an external helical groove 26 having a low pitch so that only a relatively small rotary movement will produce the desired movement of the ink cartridge in a manner to be described. I form the end of the carrier 12 remote from the threads 16 with a plurality of axially extending splines 28 for a reason which will be apparent from the description given hereinafter.

My instrument 10 as a second element of the operating mechanism thereof includes an elongated sleeve 30 formed with a bore 32 through which the cartridge 22 extends. On end of my sleeve 30 is provided with a multiplicity of internal axially extending grooves 34 adapted to receive the splines 28 to provide a connection between the carrier and the sleeve 30 which permits relative axial movement therebetween while preventing relative rotary motion. An external annular groove 36 along the length of sleeve 30 is adapted to receive a resilient snap ring 38 provided with a wall slit 40. While I have shown the slit 40 as running obliquely it might as well run axially of the ring if desired. Preferably I taper the and 42a of sleeve 30 to facilitate assembly of the snap ring on the sleeve for a reason which will be described hereinbelow.

The three parts of the operating mechanism of my writing instrument thus far described, the carrier 12, the sleeve 30 and the ring 38. may be formed of any suitable material such for example as a suitable synthetic resin. Preferably the material is one which has good dimensional ability. I have found that Delrin" which is the registered trademark of E. I. DuPont De Nemours & Co. for an acetal thermoplastic resin having high strength and stiffness, toughness and resilience over a wide temperature range as well as good dimensional stability and excellent bearing characteristics, is eminently suited for use as a material from which I may make the parts 12, 30, and 38.

The fourth and last element of the operating mechanism of my writing instrument is the driver tube 42 which may be formed from metal and provided with an internal helical bead 44 having the same pitch as the groove 26 and extending over a small portion of the length of tube 42 intermediate its ends. I form tube 42 adjacent its top with an internal shoulder 46 which limits movement of the carrier in one direction in a manner to described. Further as will be described hereinbelow in the course of assembling the operating mechanism of my instrument I provide the end of tube 42 remote from shoulder 46 with an inwardly extending flange 48.

The four parts thus far described complete the operating assembly of my instrument and are all the parts which are necessary to produce movement of the cartridge 22 between extended and retracted positions in response to relative rotary movement between driver tube 42 and the sleeve 30. For decorative purposes the instrument is completed by a shell 50 adapted to be slipped over sleeve 30 and into engagement with ring 38 with a relatively high frictional force. A nose 52 is provided with threads 54 which permit it to be threaded into the lower threaded end of sleeve 30 to force the shell 50 into position on ring 38. A cap 56 which may be provided with a pocket clip 58 frictionally fits on the driver tube 42 so that it can be relatively readily removed to permit replacing of cartridge 22 and then replaced. A decorative spacer ring 60 may be disposed between shell 50 and cap 56.

If desired I may form the driver tube with an inwardly directed projection 62 in the region of the bead 44 to increase the frictional force between the carrier 12 and the tube 42 to prevent too easy relative rotation therebetween. Further, if desired tube 42 may have a plurality of outwardly directed projections 64 to provide a relatively high-frictional force between cap 56 and the driver tube to ensure that the tube turns with the cap when the latter is rotated.

In assembling my writing instrument, I first secure the cartridge 22 to the carrier 12 by passing the cartridge 22 through bore 14 and threading the fitting onto the threads 16. Next, the sleeve 30 is assembled with the carrier 12 by inserting the splines 28 into the grooves 34. When that has been done driver tube 42 is telescoped over the assembly of carrier 12 and sleeve 30 by moving the end of the tube upon which flange 48 is to be formed over the head 24 of fitting 20 and threading bead 44 with groove 26 until the end of tube 42 remote from shoulder 46 is adjacent groove 36. The end of the sleeve is upset to form flange 48 in groove 36. It will be appreciated that the groove 36 is sufficiently wide to permit the formation of flange 48 in a relatively expeditious manner. Next, the split ring 38 is slid up along the sleeve 30 until it rides into groove 36 to hold flange 48 against the upper edge of the groove. The operating mechanism of my instrument is now complete. To finish the assembly the casing 50 is slid onto the sleeve 30 and up over the split ring 38. When this operation has continued to a point at which the lower end of sleeve 30 is accessible to the threaded portion of nose 52 the nose is threaded in place. Now cap 56 is placed on the assembly.

Referring now to FIGS. 7 and 8 I have shown a modified form of my writing instrument in which like parts to those illustrated in the form shown in FIGS. 1 to 6 are indicated by the same reference numbers. The carrier 12 and the cartridge 22 are the same as in the form of my writing instrument illustrated in FIG. 1 to 6. The sleeve 30 is slightly modified in that it is provided with an annular groove 66 between its end adjacent carrier 12 and the snap ring groove 36. Groove 66 is adapted to receive a clutching spring 68 which is formed of any suitable material such for example as stainless steel and which may be coated with a material such as Teflon" which is the registered trademark of E. I. DuPOnt De Nemours & Co. for tetraflouroethylene synthetic resin, or coated with polyethylene, resin resin or the like. Preferably I form the clutch 68 with a generally triangular configuration so that when it is assembled in groove 66 the inner surfaces of its legs engage the base of groove 66. The dimensions of the clutching spring are such that before assembly the apices hereof protrude slightly beyond the edges of the groove 66.

The driver tube 70 of this form of my device is similar to driver tube 42 but has respective outwardly directed ribs 72 extending axially of the reduced end portion thereof. These ribs cooperate with a ferrule 74 assembled within the cap 56 to insure a firm engagement between the cap and the driver tube 70. It will be appreciated that where I use the ferrule 74 I need not provide the projections 64 described hereinabove.

In assembling the form of my writing instrument illustrated in FIG. 7 the clutching spring 68 is assembled in groove 66 and splines 28 are engaged in the grooves 34. This assembly then is slid into the driver tube 70 upon which flange 48 has not yet been formed. In order to facilitate entry of the spring 68 into the bore of tube 70 I provide a special tool (not shown) having a tapered inner bore which is adapted to be slipped over sleeve 30 to a position at which it distorts spring 68 to permit it to enter tube 70. When the clutching spring has moved into the tube the assembly of carrier 12 and sleeve 30 is pushed sufficiently far into the tube 70 to permit formation of the retaining flange 48 in the groove 36. Before formation of the flange 48 the tool is of course removed. Next. a split ring having straight wall cut 82 is slid over sleeve 30 and into the groove 36. The apices of the spring 68 engage the inner surface of tube 70 to provide the required torque for relative rotation between tube 70 and sleeve 30 for proper operation of the instrument. Ferrule 74 may be assembled in cap 56 by any suitable means and then housing 50 and cap 56 together with the tip 52 may be applied to complete the assembly.

Referring to FIGS. 10 and II in a further form ofmy means for releasably holding cap 56 in position on the tube 70 I provide a reduced diameter end portion 88 of tube 70 with spaced slots 90 extending in the direction of the length of the tube. For example I may provide three slots 90 equally spaced around portion 88 by A bushing 92 formed from a suitable material such as nylon has elongated internal ribs 94 spaced correspondingly to slots 90 and adapted to engage in the slots when the bushing 92 is slipped onto portion 88. Elongated external ribs 96 at locations corresponding to ribs 94 are adapted frictionally to retain the cap 56 when it is slipped over the end of tube 70. It will be appreciated that the pairs of ribs 94 and 96 may flex inwardly when this operation takes place.

In operation of the form of my mechanical writing instrument illustrated in FIGS. 1 to 6 in response to counterclockwise rotation of cap 56 and driver tube 42 relative to casing 50 and sleeve 30 as viewed from the top of the instrument l0 carrier 12 and cartridge 22 move to the right as viewed in FIG. 3 until the end of carrier 12 adjacent threads 16 engages shoulder 46. This is the limit of the retracted movement of the carrier and cartridge illustrated in broken lines in FIG. 3. Upon reverse relative movement of the cap 56 and tube 42 relative to casing 50 and sleeve 30 carrier 12 and cartridge 22 move to the left to the limit permitted by splines 28 and grooves 34 which is the limit of the extended position of the cartridge. The operation of the form of my invention illustrated in FIGS. 7 and 8 is substantially the same.

It will be seen that I have accomplished the objects of my invention. I have provided a mechanical writing instrument which overcomes the defects of mechanical writing instruments of the type which are operated in response to rotary movement. My instrument includes a minumum of parts for the operating mechanism thereof. It is rugged in construction and has a long life. It is simple in construction and operation. It is inexpensive to manufacture.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. It is further obvious that various changes may be made in details without departing from the spirit of my invention. It is, therefore, to be understood that my invention is not to be limited to the specific details shown and described.

Having thus described my invention, what I claim is:

1. An operating mechanism for a writing instrument including combination, carrier, an elongated writing element having a point supported on said carrier for movement therewith, a sleeve, means coupling said sleeve to said carrier for rotary movement therewith and for axial movement relative thereto, a driver tube, positively interengaging elements on said driver tube and on said sleeve for connecting said driver tube to said sleeve for rotary movement relative thereto while restraining said driver tube against axial movement relative to said sleeve, said writing element extending through said sleeve, and interengageable means on said driver tube and on said carrier for moving said carrier axially in response to rotary movement of said driver tube on said sleeve to move said writing element between an extended position and a retracted position.

2. An operating mechanism as in claim 1 including means on said driver tube for limiting the movement of said carrier to said retracted position.

3. An operating mechanism as in claim 2 in which said limiting means is a shoulder on said driver tube engaged by said carrier in said retracted position.

4. An operating mechanism as in claim 1 in which said interengageable means comprises a helical groove in one of the carrier and driver tube and a helical bead on the other of the carrier and driver tube.

5. An operating mechanism as in claim 1 in which said coupling means comprise an axially extending spline on one of the carrier and sleeve and an axially extending groove in the other of the carrier and sleeve for receiving said spline.

5. An operating mechanism as in claim 1 in which said coupling means comprise a plurality of spaced splines formed on one end of one of the carrier and sleeve, and a plurality of correspondingly spaced grooves in the associated end of the other of said carrier and sleeve.

7, An operating mechanism as in claim 1 in which said interengaging elements comprise means forming an annular groove in said sleeve, an inwardly directed annular flange on an end of said driver tube located in said groove and a resilient snap ring disposed in said groove for positioning said flange in said groove.

8. An operating mechanism as in claim 1 in which said coupling means comprises an axially extending spline on one of said carrier and sleeve and an axially extending groove in the other of said carrier and sleeve for receiving said spline and in which said interengageable means comprises a helical groove in one of the driver tube and carrier and a helical bead on the other of the driver tube and carrier for riding in said groove.

9. An operating mechanism as in claim 8 in which said interengaging elements comprise means forming an annular groove in said sleeve, an inwardly directed flange on one end of said driver tube, and a snap ring in said groove for holding said flange against an edge of said groove.

10. An operating mechanism as in claim 9 including first means for limiting the movement of said carrier to the retracted position of said element and second means for limiting the movement of said carrier to the extended position of said element.

11. An operating mechanism as in claim 10 in which said first limiting means comprises a shoulder formed on said tube for engagement by said carrier and in which said second limiting means comprises said spline and axial groove.

12. A mechanical writing instrument including in combination, a carrier having a longitudinally extending bore, an elongated writing element having a point, means detachably mounting said element on said carrier for movement therewith, a spiral track formed in the outer surface of said carrier along a portion of the length thereof, a sleeve having a longitudinally extending bore, aid element extending through said sleeve bore, a spline formed at one end of one of the carrier and sleeve, an axially extending groove formed in an end of the other of he carrier and sleeve for receiving said spline to couple said carrier to said sleeve for rotary movement therewith and for axial movement relative thereto, a driver tube having an Internal helical bead, said tube adapted to receive said carrier with said bead located in said track, means forming an annular groove in the outer surface of aid sleeve, an inwardly directed flange on an end of said tube disposed in said groove, a resilient snap ring in said groove for positioning said flange against an edge of said groove, and an elongated casing adapted to he slid over said sleeve and into frictional engagement with said snap ring.

13. A writing instrument as in claim 12 including a nose secured to said sleeve for holding said casing in position on said assembly.

14. A writing instrument as in claim 12 including a cap frictionally supported by said tube for rotation therewith.

15. A writing instrument as in claim 12 including means for increasing the frictional force between said driver tube and said carrier.

16. A writing instrument as in claim 12 including means forming a second annular groove in the outer surface of said sleeve, said second groove being located between said first annular groove and the end of said sleeve adjacent said carrier and a spring clutch element disposed in said second annular groove for engaging the inner surface of said tube.

17. A writing instrument as in claim 16 in which said spring clutch is generally triangularly shaped element of resilient material.

18. A writing instrument as in claim 12 including means forming spaced slots in the wall of said driver tube adjacent the other end thereof, a bushing having internal ribs spaced correspondingly to said slots, said bushing adapted to be slipped over said other end to locate said ribs in said slots, external ribs on said bushing at locations corresponding to the locations of said internal ribs, and a cop frictionally received by said external ribs. 

1. An operating mechanism for a writing instrument including combination, carrier, an elongated writing element having a point supported on said carrier for movement therewith, a sleeve, means coupling said sleeve to said carrier for rotary movement therewith and for axial movement relative thereto, a driver tube, positively interengaging elements on said driver tube and on said sleeve for connecting said driver tube to said sleeve for rotary movement relative thereto while restraining said driver tube against axial movement relative to said sleeve, said writing element extending through said sleeve, and interengageable means on said driver tube and on said carrier for moving said carrier axially in response to rotary movement of said driver tube on said sleeve to move said writing element between an extended position and a retracted position.
 2. An operating mechanism as in claim 1 including means on said driver tube for limiting the movement of said carrier to said retracted position.
 3. An operating mechanism as in claim 2 in which said limiting means is a shoulder on said driver tube engaged by said carrier in said retracted position.
 4. An operating mechanism as in claim 1 in which said interengageable means comprises a helical groove in one of the carrier and driver tube and a helical bead on the other of the carrier and driver tube.
 5. An operating mechanism as in claim 1 in which said coupling means comprise an axially extending spline on one of the carrier and sleeve and an axially extending groove in the other of the carrier and sleeve for receiving said spline.
 6. An operating mechanism as in claim 1 in which said coupling means comprise a plurality of spaced splines formed on one end of one of the carrier and sleeve, and a plurality of correspondingly spaced grooves in the associated end of the other of said carrier and sleeve.
 7. An operating mechanism as in claim 1 in which said interengaging elements comprise means forming an annular groove in said sleeve, an inwardly directed annular flange on an end of said driver tube located in said groove and a resilient snap ring disposed in said groove for positioning said flange in said groove.
 8. An operating mechanism as in claim 1 in which Said coupling means comprises an axially extending spline on one of said carrier and sleeve and an axially extending groove in the other of said carrier and sleeve for receiving said spline and in which said interengageable means comprises a helical groove in one of the driver tube and carrier and a helical bead on the other of the driver tube and carrier for riding in said groove.
 9. An operating mechanism as in claim 8 in which said interengaging elements comprise means forming an annular groove in said sleeve, an inwardly directed flange on one end of said driver tube, and a snap ring in said groove for holding said flange against an edge of said groove.
 10. An operating mechanism as in claim 9 including first means for limiting the movement of said carrier to the retracted position of said element and second means for limiting the movement of said carrier to the extended position of said element.
 11. An operating mechanism as in claim 10 in which said first limiting means comprises a shoulder formed on said tube for engagement by said carrier and in which said second limiting means comprises said spline and axial groove.
 12. A mechanical writing instrument including in combination, a carrier having a longitudinally extending bore, an elongated writing element having a point, means detachably mounting said element on said carrier for movement therewith, a spiral track formed in the outer surface of said carrier along a portion of the length thereof, a sleeve having a longitudinally extending bore, aid element extending through said sleeve bore, a spline formed at one end of one of the carrier and sleeve, an axially extending groove formed in an end of the other of the carrier and sleeve for receiving said spline to couple said carrier to said sleeve for rotary movement therewith and for axial movement relative thereto, a driver tube having an internal helical bead, said tube adapted to receive said carrier with said bead located in said track, means forming an annular groove in the outer surface of said sleeve, an inwardly directed flange on an end of said tube disposed in said groove, a resilient snap ring in said groove for positioning said flange against an edge of said groove, and an elongated casing adapted to be slid over said sleeve and into frictional engagement with said snap ring.
 13. A writing instrument as in claim 12 including a nose secured to said sleeve for holding said casing in position on said assembly.
 14. A writing instrument as in claim 12 including a cap frictionally supported by said tube for rotation therewith.
 15. A writing instrument as in claim 12 including means for increasing the frictional force between said driver tube and said carrier.
 16. A writing instrument as in claim 12 including means forming a second annular groove in the outer surface of said sleeve, said second groove being located between said first annular groove and the end of said sleeve adjacent said carrier and a spring clutch element disposed in said second annular groove for engaging the inner surface of said tube.
 17. A writing instrument as in claim 16 in which said spring clutch is generally triangularly shaped element of resilient material.
 18. A writing instrument as in claim 12 including means forming spaced slots in the wall of said driver tube adjacent the other end thereof, a bushing having internal ribs spaced correspondingly to said slots, said bushing adapted to be slipped over said other end to locate said ribs in said slots, external ribs on said bushing at locations corresponding to the locations of said internal ribs, and a cap frictionally received by said external ribs. 